Grinding machine



Dec. 12, 1933. H ERNST 1,938,759

GRINDING MACHINE Filed Aug. 28. 1930 Patented Deen 12, 1933 ENT OFFICE GBINDING MACHINE mns Ernst, cincinnati,

cinnati Grinders Incorporated,

Ohio, a corporation' of Ohio, assignor to Cin- Cincinnati, Ohio Application August 2.8, 1930. Serial No. 478,422

, 'This invention relates to improvements in grinding machines and especially improvements in what is known as center type cylindrical grinders.

Heretofore cylindrical grinders have been utilized for the perfomance of grinding operations but considerable diiculty has been experienced in the grinding or finishing of exceedingly large and heavy work pieces, such as rolls employed in rolling mills, paper mills or the like. This diillculty resulted chiey from the mechanism heretofore used for rotating said rolls which mechanism caused out of round or egg shaped rolls to be produced.

It is, therefore. one of the principal objects of this invention to provide a driving connection between the work or roll and the spindle of the machine whereby the said roll will be positively driven at a uniform rate and about a dennite, unvarying axis to insure the cylindrical production of the work.

Another object of this invention is the provision of an equalized drive for rotating cylindrical work which automatically equalizes or balances the torque on the driving'members thereby insuring the positive rotation vof the roll and preventing lateral sway or displacement thereof.

Otherobjects and advantages of the present invention should be readily apparent by reference 3 to the following speciiication considered in conjunction with the accompanying drawing and it is to be understood that any' modiilcations may be made in the structural details there shown within the scope of the appended claims without departing from or exceeding the spirit of the invention.

In the drawing:l

Figure 1 is a fragmentary elevational view of a grinding machine embodying the improvements of this invention.

Figure 2 is a sectional view takeneo-line 2-2 of Figure 1.

Figure 3 is a sectional view ,taken on line 3-3 of Figure 2. v Figure 4 is a sectional view on line 4--4 of Figure 1.

Throughout the several views of the drawing similar reference characters are employed to denote the same or similar parts.k

.As was noted above, cylindrical grinders as whole are not new and the grinding machine per se forms no part of this invention. Such a machine may Acomprise a bed 10 having mounted thereon a work supporting table 1l longitudinal- 1y actuable relative to the bed on ways 12. The

7 y (Cl. 51-236) table 11 supports at one end avheadstock 13 and at the other end a tailstock 14 between'which the work is positioned. The work 15, here shown as a relatively large roll as employed in rolling mills or the like, is supported for rotation on journal supports 16. The journal supports 16 have an underi'ace 17 engaging a similarly formed face 18 on the table 11 and have contact shoes 19 and 20 at their upper end for actual contact with the surfacevof the work`^15. As shown in Figure 4, the shoes 19 and 20 are adjustable as by adjusting screws 21 for varying the size of work that may supported between them.

The work piece or roll 15 is provided on opposite ends with journals 22 and supported by journal supports 16 and the roll is formed on one end adjacent one of the journals with a wabble drive 23. This wabble drive end 23 is formed with arms 24 extending on opposite sides thereof.

In the past a driving connection has been utilized for rotating the roll 15 through the wabble drive end 23 but the power was applied to but a single point thereof due to its particular construction. This resulted in a tendency of the work to pivot first about one of the journal shoes y19 or 20 and then about the other resulting in a work piece having anout of round or egg shaped cross section. Referring to Figure 4 and assuming the work to be rotating in the direction of the arrow thereon, it will be seen that with the point of application of'power to the roll anywhere within the upper portion of the roll there is a tendency to pivot the roll about the journal-shoes and draw the roll away from the grinding wheel. Similarly, with the point of application of power to the roll in the lower portion thereof the tendency is to crowd the roll against the grinding wheel thereby producing a roll of oval or egg shape cross section since opposite sides or segments are alternately pushed into the grinding wheell and actuated away from the grinding whee By this invention the application of power for from the pulley 26 to a pulley 28 fast on the end of worm shaft 29. 'I'he said shaft 29 is journaled in the walls of the headstock housing and is provided intermediate its ends with a worm 30 meshfrom which ears 37 extend being adjustably secured to the face plate 33 by bolts or the like 38 extending through the said ears 37 and received in T-slots 39 formed in the said face plate 33. The dog housing 36 is bored to form a cylinder in which piston 40 is mounted for reciprocation therethrough from which pin 41 extends, A cap 42 is secured to the open end of housing 35 having a filling opening 43 formed therein and controlled by a check valve 44. An automatic filling plug 45 is also secured in the reduced end of the cap 42.

The housing 36 is further provided with conduits 46 and 4'7 at right angles to one another and communicating with the interior of the cylinder 35. A pipe or conduit 48 extends between the dogs or cylinders 34 and 35 for conveying asubstantially noncompressible medium, such as oil, grease or the like.

A supply of the said oil, grease or the like is introduced into cylinder 35 through the filling part or fitting 45 and finds its way through conduits 47, 46 and 48 to the cylinder 34 for applying equal pressures on the outside of pistons 40 contained within the said housings or cylinders 34 and 35.

As shown in Figure 2, the plungers or pins 41 are adapted to engage opposite surfaces of arms 24 at points diametrically opposed to one another. ri'iiese points should be preferably equally distant from the center of spindle 32 and work 15.

The operation of the device is as follows:

Assuming a work piece to be mounted on the journal supports 16 with the wabble drive portion 23 thereof toward the headstock and the pins 41 projecting toward the faces of the arms 24. The motor 25 is now energized which will cause a rotation of face plate 33 and driving dogs 34 and 35. Should one of the pins 41 extend further from its housing than the other it will of course, engage its arm 24 first but no movement of the work will take place because the pin engaging the arm will be pushed back into its housing. This inward movement of the pin will carry with it its attached piston forcing from the cylinder or dog housing the medium on the other side of the piston which extruded medium passes through conduit 48 into on one ofthe dogs than on the other the piston at this point will be forced into its housing forcing therefrom the hydraulic medium therein and forcing outwardly the other piston and driving pin. From this it will follow that there is no tendency of the work to pivot about journal shoes 19 and 20 thereby insuring a constant uniform rotation of the work about a predetermnfd axis resulting in the work being ground absolutely concentric with its axis.

What is claimed is:

1. In a device of the class described the combination of a face .plate adjacent the end of a work piece, adjustable dogs carried by the face plate for engaging the work at a plurality of equally .spaced drivingpoints, said dogs each comprising a cylindrical housing, a driving pin extending therefrom, a hydraulic medium between the cylinders for transmitting the pressure from each cylinder to the remaining cylinders for equalizing the pressure in said driving dog cylinders and thereby equalizing the effective urge of each driving pin, and a spring loaded valve for retaining the medium in said cylinders yet whereby the medium therein may be replaced.

2. In a grinding machine for grinding large rolls having finished journal bearings and a wabble drive end adjacent one of the bearings the combination of a bed, journal supports carried thereby for receiving the journals of the roll for supporting the roll for rotation about a predetermined axis, a work supporting table reciprocably mounted on the bed, a head stock and a tail stock on the table between which the work is disposed, a driven face plate carried by the head stock adjacent the wabble drive end, said wabble drive end comprises arms extending at angles to one another, a pair of driving dogs projecting from the face plate for engaging the arms at equally radially spaced points from the center of the roll, and means for equalizing the torque on each driving dog.

3. In a grinding machine for grinding large rolls having finished journal bearings and a wabble drive end adjacent one of the bearingsthe combination of a bed, journal supports carried thereby for receiving the journals of the roll for supporting the roll for rotation about a predetermined axis, a driven face plate adjacent the wabble drive end, said wabble drive end comprises arms extending at angles to one another, a pair of driving dogs extending from the face plate for eni' gaging the arms at equally radially spaced points from the center of the roll, and means for equalizing the torque on each driving dog, said means comprising a substantially non-compressible hydraulic medium for equalizing the total driving torque on the driving dogs.

4. In a grinding machine for grinding large rolls having a wabble drive end the combination with means for supporting said roll for rotation about a definite axis, of means for effecting its rotation comprising a driven face plate, a pair of driving dogs, means securing the driving dogs to the face plate for adjustment relative thereto radially of the axis of rotation of the roll, a driving pin extending from each dog engaging the wabble drive end of the roll at points equally spaced from the axis of the rollyand means for balancing and equalizing the torque on the driving dogs and pins.

5. In a grinding machine for grinding large rolls having a wabble drive end the combination with means for supporting said roll for rotation, of means for effecting its rotation comprising a driven face plate, a pair of driving dogs radially spaced thereon for movement therewith, each driving dog comprising a cylinder adjustably secured to the face plate, a piston within each cylinder, a driving pin carried by each piston and engaging the roll at points equally spaced from the axis of the roll, and means connecting the cylinders for transmitting the torque acting against one of said dogs to the other thereby equalizing the torque on each dog and eiecting a rotation of the roll about a predetermined, unvarying axis. I

6. In a grinding machine for grinding large rolls having a Wabble drive end the combination with means for supporting said roll for rotation, of means for eiecting its rotation comprising a driven face plate, a pair of driving dogs radially spaced thereon for movement therewith, each driving dog comprising a cylinder adjustably secured to the face plate, a piston within each cylinder, a driving pin carried by each piston and engaging the roll at points equally spaced from the axis of the roll, a conduit connecting the cylinders, and a substantially non-compressible hydraulic medium in the cylinders and conduit for transmitting the torque from one driving pin and its piston to the other.

hydraulic medium in the cylinders and conduity for transmitting the torque from one driving pin and its piston to the other, and means for introducing the hydraulic medium into the cylinders and connecting conduit.

HANS ERNST. 

